Lawmakers in the former Soviet country voted narrowly to overturn legislation passed in June that would have made it illegal to distribute information about homosexuality to children.
They voted to remove a clause that barred the promotion of "relationships than those linked to marriage and the family", which had been strongly supported by the Orthodox Church in the majority Christian country.
The Moldovan government hopes next month to initial an Association Agreement at an EU summit in Vilnius, a formal step on the road to EU membership, despite opposition from Moscow.
Several dozen Christians holding crosses and icons protested outside the parliament building ahead of the vote and tried to block lawmakers from entering.
"Today they are allowing this propaganda and tomorrow they will allow gay marriages," priest Ghenadie Valuta told reporters.